In the 3rd Generation Partnership Project (3GPP), a radio access method and a radio network for cellular mobile communications (hereinafter referred to as “Long Term Evolution (LTE)”, or “Evolved Universal Terrestrial Radio Access (EUTRA)”) have been considered. In LTE, a base station device is also referred to as an evolved NodeB (eNodeB), and a mobile station device is also referred to as user equipment (UE). LTE is a cellular communication system in which an area is divided into a plurality of cells to form a cellular pattern, each of the cells being served by a base station device. A single base station device may manage a plurality of cells.
LTE supports a time division duplex (TDD). LTE that employs a TDD scheme is also referred to as TD-LTE or LTE TDD. TDD is a technology that enables full duplex communication in a single frequency band by performing time division multiplexing on an uplink signal and a downlink signal.
In 3GPP, discussion regarding further expanding TD-LTE is taking place. For example, discussion regarding further expanding the uplink-downlink configurations that are configurable under present TD-LTE is taking place.
NPL 1 proposes, as a supplemental uplink-downlink configuration, an uplink-downlink configuration where all subframes in a single radio frame are configured as downlink subframes (downlink only configuration/10:0 configuration/supplemental downlink configuration).